Long Exposures

Longer exposures are a doorway into another world, showing us how even familiar scenes can look much different when photographed over periods measured in seconds. At night, long exposures produce streaks of light from moving, illuminated subjects like automobiles or amusement park rides. Extra-long exposures of seemingly pitch-dark subjects can reveal interesting views using light levels barely bright enough to see by. At any time of day, including daytime (in which case you’ll often need the help of neutral-density filters, which reduce the amount of light passing through the lens, to make the long exposure practical), long exposures can cause moving objects to vanish entirely, because they don’t remain stationary long enough to register in a photograph.

Three Ways to Take Long Exposures

There are actually three common types of lengthy exposures: timed exposures, bulb expo sures, and time exposures. The EOS T3i offers only the first two, but once you understand all three, you’ll see why Canon made the choices it did. Because of the length of the exposure, all of the following techniques should be used with a tripod to hold the camera steady.